Miniaturized pressure sensors and acoustic signal transducers such as microphones or loudspeakers are used for various applications, for example for acoustic component parts in portable telecommunications devices.
The sensors and actuators can in this case be produced from microelectromechanical structures (MEMS, “microelectromechanical systems”).
Such sensors and signal transducers can be based on the capacitive principle of action, i.e. voltage is applied to two membrane elements arranged with a predetermined geometry with respect to one another. By changing the voltage, movements of the membranes relative to one another can be induced. Alternatively, externally induced membrane movements can result in detectable changes in the capacitance and therefore in the voltage present.
The document DE 102 47 847 A1, for example, discloses a method for producing a membrane for an MEMS component comprising a mating electrode on a substrate. The document DE 10 2006 055 147 B4 discloses a method for producing an acoustic signal transducer structure comprising an oscillatory membrane over a mating electrode on a substrate. The document EP 2 071 871 A1 discloses a membrane for an MEMS component part comprising a corrugated peripheral region for reducing mechanical stresses of the membrane.
There is a need for membrane arrangements, in particular for microelectromechanical acoustic signal transducers, with which the sensitivity of the signal pickup can be improved and the installation space requirement can be correspondingly reduced.